Grist-mill.



PATENT oEEroE.

ROBERT F. D AVIS, 0F MORLEY, MISSOURIY GnIsT-MILL. I

Specification of Letters Patent.

patented oet. 17, i916.

Application led January 3, 1916. Serial No. 69,975.

To all 'whom t may camerati 'Be it known that I, ROBERT F. DAVIS, a

citizen of the United States, residing at Morley, inthe county of Scottand State of Missouri, have invented a new and useful Grist-Mill, ofwhich the following is a specification.

The deyice forming the subject matter of this application is a gristmill adapted to be employed for grindingv grain and like material, thestructure beingl intended primarily although not exclusively forvdomestic use. g

The invention aims to improve the construction of the burs, to providenovel means for adjusting the positions of the burs, to

provide novel vmeans for rotating the burs, and, generally, to improveand to enhance the utility of devices of'that type to which the presentinvention appertains.

With the aboveand other objects in vieW which Will appear as thedescription pro-v ceeds, the invention resides in the combination andarrangement of parts and in the details of construction hereinafterdescribed and claimed, it being understood that changes in thel preciseembodiment of the invention herein disclosed can be made Within thescope of What is claimed, Without de parting from the spirit of,theinvention.

In the accompanying drawing :-'-Figure l shows in longitudinal section,a grist mill embodying the present invention, parts appearing inelevation; Fig. 2 is a side elevation of the grist mill forming thesubject matter of this application; Fig. 3 is a horizontal 'section ofthe grist mill, parts ap pearing in elevation; Fig. 4 is a diagramVshowing one of the burs. s

In carrying out the present invention there is provided a supportingstructure '1\ on which is'mounted a bed plate 2,the latter being held tothe supporting structure by means of securing elements 3. Formedintegrally With thebed plate 2 is a circular body 4 having in itsopposite sides, frusto-conical bores 5, the smaller endsof which lieadjacent the vertical axis of the body 4. At the ends of the bores 5,

recesses 6 are fashioned, and from the recesses 6 lead discharge chutes7. Above the bores 5, the body 1 is provided with a conical bottom 8 atthe lowermost point of Which is disposed an opening 9. communicatingwith the bores 5. At its upper end, the body 4 is provided with a flange10 retaining a hopper 11. yThe body 3 i's surrounded by a pair .ofapproximately semi-circular casing members l2 provided with ribs 28received in recesses 29 formed inthe body 4, tohold the casing membersin place. The

casing members 1 2 are supplied with fillets' A14 from whichprojectpears 15 connected #by bolts 16, the casing hnembers 12 beingthus held about the -body\4 to constitute closures for the recesses 6.'y

Threaded into the casing members 12 and projecting into the recesses arebearings 17 provided with hand Wheels 18, whereby the bearings maybemoved endWise for apurpose to be pointed out hereinafter. :The bearings17 may be held in adjusted positions by means of lock nuts 19 threadedonto the bearings and adapted to bear against the casing members 12. Journaled for rotation in the bearings 17 is a main shaft 20, providedatone end With a pinion 21 carrying a flange 22. lThe pinion 2l meshesinto an internal gear 23 lformed on a drive Wheel 24 journaled forrotation on a stub shaft 25 projecting from alug 26 constituting a partof the body 4, the Wheel 24 being held on the stub shaft 25 by means ofa nut 27 or the like. The flange 22 coacts With the `inner edge of theWheel 24 and constitutes a means whereby the main shaft 20 is preventedfrom moving to the right, referring to Fig. 1. The drive Wheel 24 maybe. r0- tated through the medium of a handle 30 or, if desired, a belt(not shown) may be trained aboutthe periphery of the Wheel 24, When itis desired to drive the Wheelfrom ya gasolene engine orother primeymover. Secured to one end lof the main shaft 20 is a gear Wheel 31meshing into a pinion 32 fixed to a shaft'33 journaled for rotation inthe supporting structure 1. The

pinion 32 is provided with an outstanding flange 34, adapted to coperateWith the outer face of the gear Wheel 31, thereby to limit the movementof the main shaft 2O toward the left, referring to Fig. 1. Secured toone end of the shaft 33 is a fly Wheel 35. The'shaft 33 may bel employedfor driving a bolting. mechanism, but since such a structure cannot beclaimed in the present application, along with a grinding means,` nobolting mechanisml has been shown or described.

Surrounding a portion of the main shaft 20 and located in thefrusto-conical bores 5 of the body 4 are frusto-conical burs 36 pro-`-from each other.

vided internally with recesses 37. The burs 36 are held to the mainshaft 20 for rotation therewith, through the instrumentality of keys 38,the construction being such that, through a mechanism to be describedhereinafter, the burs 36 may be adjusted toward and away from eachother, the burs sliding longitudinally of the keys 38. The burs 36 areprovided with teeth 39, the teeth being spaced more` widely from eachother adjacent the smaller ends of the burs than adjacent the wider endsofthe burs, as indicated diagrammatically in Fig. 4. The frusto-conicalbores 5v in thev body .4 are equipped with suitably shaped teeth,indicated at 40 and adapted to coperate with the teeth 39 on the burs.Applied to the ends of the burs 36 areend plates 41 held in place bysecuring elements 42. within the recesses 37 of the burs 36 arecompression springs 43, the inner ends of which bear against the keys38, the outer ends of which bear against the end plates 41. The endplates 41 areengaged by the.threaded ,bearings 17.

In practical operation, the material to be ground is dumped into thehopper 11 and passes by way of the opening 9 into the frusto-conicalbores 5, the material therein being macerated or ground by the action ofthe teeth 40 in the bores 5 and the teeth 39 on the burs 36. The groundmaterial flows into the recesses 6 and leaves the recesses 6 by way ofthe chutes 7.

Rotation is imparted tothe main shaft 2O and to the burs 36 by means ofthe pinion- 21 and the internal gear 23 of the-drive wheel 24, it beingobserved that when the drive wheel :24 is rotated in a clockwise di'rection, the main shaft 20 and the burs 36 will be rotated in aclockwise direction also.

The ineness of the grist may be regulated by adjusting the burs 36toward and away The springs 43tend to move the burs 36 outwardly, awayfrom each other, thereby to increase the coarseness of the grist. Inorder to move the burs 36 toward each other, thereby to render the gristfiner, the bearings 17 are rotated, the same advancing and bearing uponthe end plates 41, the burs-36 thus being thrust towardeach other. Thebearings 17 may be held in adjusted positions by manipulating the locknuts 19, so that the same bear upon I-Ioused the casing members 12ashereinbefore described.

Having thus described the invention. what isclaimed is y l. In a gris-tmill, a. body provided with opposed frusto-conical bores, the smalleiends of which are disposed adjacent the vertical axis of the body;opposed screws threaded into the body; nuts on the screws and coactingwith the body; a` shaft journaled for rotation in the screws; `opposedfrusto-conical burs secured to the shaft to rotate therewith, andlocated in the bores, the burs having recesses in their outer ends;compression springs in the recesses and coacting at their inner endswith the shaft; and removable closures for the recesses and located onthe outer ends of thc burs, the closures being engaged by the screws,and constituting abutments for the outer ends of the springs.

A grist mill comprising a body; a shaft journaled for rotation in thebody; burs slidable longitudinally.of the shaft and operating within thecontour of the body: springs engaged at their outer ends with the burs;means on the shaft for receiving the inner ends of the springs; meansfor limiting the outward movement of the burs; a drive wheel journaledfor rotation on the body and provided with an internal gear; a pinion.carried by the shaft and meshing with the internal gear. the pinionhaving a flange coacting with the inner edge of the drive wheel, therebyto prevent the shaft from moving inone. direction due to unequal effortsof the springs; a second shaft journaled for rotation in the body; agear wheel carried by the first specified shaft; a pinion carried by`the second shaft and meshing into the last specified gear wheel, thesaid pinion being provided'with a fiange coacting with the outer face ofthe last specified wheel, to prevent the irst mentioned shaft frommoving in an opposite direction due to unequal efforts of the springs.

In testimony that I claim the foregoing as my own, I have hereto affixedmy signa-.

ture in the presence of two witnesses.

ROBERT F. DAVIS.

Witnesses:

R. H. TERRY, J. H. DAVIS.

